[SPARK-23603][SQL]When the length of the json is in a range,get_json_object will result in missing tail data

[cxzl25]

What changes were proposed in this pull request?

Bump jackson from 2.6.7&2.6.7.1 to 2.7.7
Jackson(>=2.7.7) fixes the possibility of missing tail data when the length of the value is in a range
https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.7.7
https://github.com/FasterXML/jackson-core/issues/30

spark-shell:

val value = "x" * 3000
val json = s"""{"big": "$value"}"""
spark.sql("select length(get_json_object(\'"+json+"\','$.big'))" ).collect
res0: Array[org.apache.spark.sql.Row] = Array([2991])

expect result : 3000
actual result : 2991

How was this patch tested?

org.apache.spark.sql.catalyst.expressions.JsonExpressionsSuite
test("some big value")

[cxzl25]

Another solution:
#20739

[AmplabJenkins]

Can one of the admins verify this patch?